Properties

Label 2.61.ac_dj
Base field $\F_{61}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple no
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{61}$
Dimension:  $2$
L-polynomial:  $( 1 - 7 x + 61 x^{2} )( 1 + 5 x + 61 x^{2} )$
  $1 - 2 x + 87 x^{2} - 122 x^{3} + 3721 x^{4}$
Frobenius angles:  $\pm0.352090495177$, $\pm0.603713893500$
Angle rank:  $2$ (numerical)
Jacobians:  $336$

This isogeny class is not simple, primitive, ordinary, and not supersingular. It is principally polarizable and contains a Jacobian.

Newton polygon

This isogeny class is ordinary.

$p$-rank:  $2$
Slopes:  $[0, 0, 1, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $3685$ $14493105$ $51553680640$ $191709358025625$ $713356084903367125$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $60$ $3892$ $227130$ $13845988$ $844611900$ $51519778342$ $3142739754060$ $191707360046788$ $11694146324309250$ $713342909874316852$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 336 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{61}$.

Endomorphism algebra over $\F_{61}$
The isogeny class factors as 1.61.ah $\times$ 1.61.f and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:

Base change

This is a primitive isogeny class.

Twists

Below is a list of all twists of this isogeny class.

TwistExtension degreeCommon base change
2.61.am_gb$2$(not in LMFDB)
2.61.c_dj$2$(not in LMFDB)
2.61.m_gb$2$(not in LMFDB)